Fluid coupling



y 3 1945- V v w. WOLFRAM v2,380,681

' FLUID COUPLING FiledMay 29, 1942 s Sheets-Sheet 1 omega y 1945- w. s. WOLFRAM 2,380,681

FLUID COUPLING Filed May 29, 1942 5 Sheets-Sheet 2 L, AQ I.

Ihwentor July 31, 1945. 1

W. S. WOL FRA M FLUID COUPLING 3 Sheets-Sheet 3 Filed May 29, 1942 Patented July 31, 1945 UNITED STATES PATENT omcs FLUID COUPLING William S. Woli'ram, Scotch Plains, N. 3.. assignor to General Motors Corporation, DetroihMioh a corporation of Delaware Application May 29, 19 42, No. 445,036

use of a clutch employing a fluid medium of high specific gravity. v I

An important associated object is foundin the provision for clutch release in the form of an inherent part of the fluid clutch thereby to avoid the need for an associated releasable friction clutch arranged in series with the fluid clutch.

Another object is the provision of means acting automatically to prevent a. car equipped with the fluid clutch from rolling down grade,

The invention includes the provision of hydraulic means whereby the clutch may be released and yielding means to normally maintain the clutch parts in driving relation.

Other objects dnclude structural arrangements which shall be eil'ective yet simple and comparativeLv inexpensive.

Still other objects and advantages'will appear from a readingof the description which follows. On the drawings: 1

Fig. 1 is a transverse section through one embodiment of the invention.

Fig. 2 is a similar view of a modified form.

Fig. 8 is a view in elevation partly broken away At 3! a shown a bronze bearing. It is pressed into the flanged central hole in flywheel member 2|. Bearing 31! provides a close his with shaft 9 but not such as to prevent relative rotation between the flywheel and the shaft. The bearing supports the flywheel and acts also as a retainer forv oil. Additional sealing means is used to supplement such oil sealing as is ailorded by bearing 3?. ring 39 of bronze and a corrugated disc H of metal. The outer edge of disc ll is fastened to flywheel member 2| and the inner edge is shapedto fit the forward and inner faces of ring 89. A conical spring 43 is arranged in abutment with part 2i and disc 4! to hold the disc in tight engagement with the ring 39 and the latter against a collar 45 of metal which is assembled on shaft 9 to prevent leakage.

On the inside of flywheel member I9 is an. annular steel ring 41 secured by the attaching means 28. Ring 41 is positioned within the walls of a ring is which is channel shape in section and has inner and outer flanges Ii and 53 respectively.

and in section the plane of the view beingindicatedonFlg.2byline3--3.'

Referring to the drawingsin connection with this description, it will be seen that numeral 5 represents a more or less conventional housing for a clutch which is to connect an engine shaft I with a ton shaft Q. Numeral ll represents a flange 'on shaft 1 and to it is secured by cap screws I! asteel stamping II. The flywheel is designated as a whole by numeral II. It is made from two halves I! and II joined together at their edges 23 and 25. The two edges may be 'welded to an internally positioned band 21 to make an oil-tight Joint. Part I! of the flywheel is secured to stamping I! by cap screws 29. To seal the Joint between parts I! and I! there is seenaringot lead 3|. A ring 33 carries theusual ring gear 38', ring 33 being welded to ring gear 35 and to the flywheel member I9.

The ring 48 is fastened to the flywheel member l9 and the ring 41 by welding or otherwise. A plurality of channel-shaped pieces 55 are welded to ring so.

Within the flywheel is a hub 51. It is to slide axially on the splines 59 of transmission shaft 0. To the hub 51 are secured rings BI; 63 and of steel. Parts 83 and 85 are attached to hub 51 by rivets '1. A plurality of flns 69 preferably steel stampings of channel shape in section arefastened to the inside surface of the rings Cl, 63 and ll. A spiral flange ll surrounds and is secured to the outer surface of ring. OI. It completely surrounds the ring and may be of one or more pieces.

Hub I1 slidable on the shaft splines .50 is limited in its rearward movement by engaging bearing 81. A collar 15 is attached to the front and of hub 61 as by welding. A pin 1'! slides within an axial opening I! of shaft 8. It also slides in a. hole Si in the crankshaft, where it is supported by roller bearings ll. The pin is sealed against leaks by rings II. The collar I5 is secured to the pin TI by a'rivet 81. A bronze bearing Washer 89 is press fltted into the rear end of the crankshaft. A spring seat ti bears against washer 89 and receives one end of a coil spring 93, the other end of which is seated on a shoulder of hub 51.

A collar 91 of steel is assembled on shaft 9. It is provided with a radial hole 99 which registers with an annular groove III formed on the The additional sealing means includes a shaft. Collar 01 is held in place by collars ll and I03 which are tightly screwed to collar 81. there being clamping lead rings as shown to seal the joint. Between rings 45 and III are discs IIS and I". A sylphon type of wall II. is securely sealed by silver solder or otherwise to the discs I" and ill. The discs III and Ill are'held apart by a spring ill to provide pressure to hold hearings H8, H5 secured thereto tightly against the collars It and I. At III isapinproiectingfromhousingland disc II] to prevent any tendency of the parts Ill! and I" to rotate. The shaft 9 has'radial and axial n *1 ii! and III affording communication between groove llll and the space 1:. At I2: is a fitting for connection with a conduit for supplying fluid under pressure from any suitable fluid pump or master cylinder not shown.

The flywheel is to be partly fllled, perhaps Theinsidesurfaceofflangellisthreadedtose-' cure a collar ll. The outeredge of collar is provided with an outwardly extending radial flange II which is formed with notches to receive a spanner wrench. At the opposite edge is an inwardly directed flange SI to which is fastened by silver soldera sylphon sleeve 52. To the opposite end of the sleeve 52 is soldered a bearing .with the sylphon collar is coilspringit whichbearsagainst collar and 80%, with a heavy oil of such viscosity as'will be suitable for a wide temperature range.

when the flywheel isinactiontheoil is thrown outwardly and revolves .with it and influenced by the rotating channel member I5.

causes the driven memberthe hub I] and connected parts to rotate and thus produce a rota.- tion or the on shaft. In further explanation of the operation it will be seen that spring ll is holding the drivenrotor elements ringlltoholdtheringlltightlyasainstaflange orcollar l8 whichissecuredtoshaft ll. Asnap ringiilinagroove of the shaft servestohold the collar". Acollarflwithinternalthreadsisalso secured to the shaft ll somewhat tothe rear of collar 8. Between these collars and closely flt tingtheonshaftilisaspacingcollar ll. It istightly clamped between collars It and I! there beingsealinggaskets ti. Oolla'rflhas an annular groove .8 connecting by a hole II with the outer surface. Also between collars I -and I2 is a bellowsunit toform a closure comthe spring 93 returns the parts to the operative position. In so returning the parts the fluid within the flywheel actingon the spiralflns'll one is; 3.1. I Whentheclutchisreleasedthefluidpressure withinandbetweenthediscs-ill and ill presses the non-rotating parts Ill and lil against the parts II and III rotating with shaft l and the friction tends to overcome the inertia of the drivenshaftandbi'lngittotest.

For use inthe hydraulic clutch I prefer to use an oil with colloidal lead in suspension whereby the specific gravity is increased and to affordlubrication.

A second embodiment of the invention .is

mmicating with external hydraulic means and the internal passages for clutch re- 88 and 82. The bellowsunitalsoaatctsasabrakev when the clutch is released because of the pressure between rings 82 and collars st and 8!. There area plurality of lugs ll welded to flate It. These lugs are fastened to matching lugs on caps! which is fastened to the tron housing by screws II. The unit is thus held in flxed position. It is provided with a threaded shown inri'g. 2. In thisform the housing con-- 7 tains the fluid clutch for coupling the engine shaft 8 with the transmission-shaft II A plate I! is secured to the flange ll by fastening means It, there-beinguseda sealing gasket It. .The plate il'carries the usual ring gear 2|. The flywheel proper includes a plate 22 and a bowl-likecaaing fastened together .by welding their to] make a leak-proof .ioint. The wall of casingflmay be corrugated or fluted as at}! to add rigidity and to constitute a means to circulate air outside the flywheel and within the housing i for cooling. On the inside of casing It and secured to plate It .i a ring 20 to which are assembled and fastenedby 'weldinga plurality of firm I. which are of channel shape in section. vA plurality of lugs; flareweldedtoringis. 'lheflywh lpropersocket ll to which the conduit of a system may be. I

'Within' the flywheel is the driven rotor correspondingtothedrlvenplateblyofaconventional friction clutch. Huh .2 slides on splines of shaft ll. Hub 02 has a reduced end which entersfreelywithintheend ofbearinglii. Bythis arrangement the on shaft ll may be hydraulic withdrawn from the flywheel as may be for service without disturbing the fluid flywheel.

-Aringiafastenedtothehub. Toringfl are welded a plurality of fins at which fit withsufllcientclearanceintoanannularrecessintheassemblyofflnsll. Therotorisshowninthe figureintheclutchengagedposition. ltis o .heldbyaspringllengasinshub nandasmtscribed. Thisactioniseifectedbyfluidunder' pressmen'omasuitablesourcebeingforced through opening OI andinto thespace between plates It and I4, through es Ill andillinthedrivenshaftandintoacyiindrical" chamber illyvithinwhichslidesapinorpiston H connected as before by a rivet Hz to a yoke I I4 connected to the hub. The end of the piston slides within bearings H6 in the engine shaft 8.

The spring 98 may be provided with a flanged rotor is in driving position it is forced to rotate.

When the fins 9,6 are projected into the core I02, the drive is discontinued. At that time the fluid within the sealing bellows I6 causes parts 82 to frictionally engage the parts 58 and 62 to check the rotation of the shaft Ill due to the inertia of the parts connected thereto.

A spaced fin 522 carried by plate 94 is acted upon by the fluid in the flywheel and aids the spring 98 in effecting reengagement of the clutch after release. As explained above in service the projecting ends of hub 92 and bearing 40 provide for the removal of shaft l 0 without disturbing the fluid clutch.

It may be desirable to provide means to hold the car parked on an inclined surface by means of the engine acting as a brake. To that end a plurality of pawls a are pivoted to the rotor, each on a pivot b. A spring 0 acts on each pawl to push it outwardly to locking position. The other end of the pawl is weighted as at d. The spring is so designed as to overcome the centrifugal force acting on the-weighted end only when the rotor speed is 40 r. p. m. or less. Asimilar set of pawls e is carried by the flywheel member 24. They, too, have weights and a spring g. The interenga'gement requires the rotation of the flywheel jointly with ,the rotor. Since the flywheel is connected to the engine, the engine serves as a brake to prevent rotation of the rotor and the forward movement of the car .downgrade.

I 'claim:

1. In combination, a driving member, a driven member, a hollow flywheel carried by the driving member, said driven member projecting into said hollow flywheel, a fluid clutch to couple said flywheel and driven member and including first and second parts non-rotatably connected to the flywheel and driven member, said first part having fins and an inner core, spring means to move said parts into operative relation and other means operable to effect relative movement of said parts whereby the fins of the second part enter said core, one of said parts having ahub reciprocable on said driven member and said spring means surrounding and engaging said hub, together with a pawl on the flywheel and a cooperating pawl on that part of the coupling associated with the driven member whereby power means/for driving the driving member may act as a brake to check rotation of the driven member.

2. In combination, a driving member, a driven member, a hollow flywheel carried by the driv ing member, said driven member projecting into said hollow flywheel, a fluid clutch tov couple said flywheel and driven member and including first and second parts non-rotatably connected to the flywheel and driven member, said first part having fins and an inner core, spring means to move said parts into operative relation and other means operable to effect relative movement of said parts whereby the flns of the second part enter said core, one of said parts. having a hub reciprocable on said driven member and said spring means surrounding and engaging said hub, together with a pawl on the flywheel, and a cooperating pawl on that part of .the coupling associated with the driven member whereby power means for driving the driving member may act as a brake to check rotation of the driven member, said pawls being weighted" to effect disengagement under the action of centrifugal force thereon and springs operable on said pawls to effect engagement of said pawls at low speeds of rotation.

3. In combination, a driving member, a driven member, a releasable fluid clutch to couple said members, said clutch comprising a first part having a set of C-shaped fin formations forming interrupted channels and an inner core, a second part having a set of fin formations, means to connect said two formations one to the driving member, the other to the driven member, spring means to effect relative movement of said two parts into registration for driving and other means -to effect an opposite relative movement whereby said second set occupies the core of the first set, said other means including a reciprocable fluid operated piston in said driven member, connections therefrom to one of said parts and conduit means to supply fluid pressure to said piston, said conduit means including movable walls forming a closed space and friction members carried by said walls to engage cooperating rings carried by and rotatable with said driven member.

4. In combination, a driving member, a hollow flywheel secured thereto, a driven shaft projecting into said flywheel, fluid coupling means connecting said flywheel and driven shaft and including a hub reciprocable on said driven shaft, a bearing carried by said flywheel and closely embracing said driven shaft, said reciprocable hub and bearing having overlapping regions whereby said shaft may be removed without disturbing said fluid coupling.

5. In combination, a driving member, a driven member, a fluid clutch to couple said members, hydraulic means to release said clutch and friction means operable in response to the actuation of said hydraulic means to retard rotation of said driven member when releasing the clutch said hydraulic means including an expansible chamber having a movable wall, said friction means including a part rotatable with said driven member and a non-rotatable part movable in response to the expansion of said cham-' ber to frictionally engage said rotatable part.

6. In combination, a driving member, a driven member, a hollow flywheel carried by the driv-' the driven member and a second part movable in response to the expansion of said chamber into frictional engagement with said first part to retard the rotation of the driven member.

7. The invention defined by claim 6, said hydraulic means including a piston slidable in an axial bore of said shaft, means connecting said piston to said slidable element and passages in an external source to said axial bore.

8. In combination, a driving member, a driven member, a hollow flywheel carried by the driving member, said driven member including a shaft projecting into said flywheel, a fluid clutch within said flywheel for coupling said flywheel to said shaft, said fluid clutch including a turbine element and a rotor element one of said elements being slidable on said shaft, yielding means to efiect relative movement of said'elements to operative position, hydraulic means to overcome said yielding means and effect relative movement of said elements to inoperative position, said hydraulic means including a piston slidable in an axial bore of said shaft, means connecting said piston to said slidable element and passages in said shaft for supplying hydraulic pressure from an external source to said axial bore, said hydraulic means also including a non-rotatable annular sealed space having movable walls surrounding said shaft and friction means carried by the walls of said space and said shaft to retard rotation of said shaft under 15 the influence of hydraulic pressure.

WILLIAM S. WOLFRAM. 

